1. Field of the Invention
The present invention relates to outdoor and patio umbrellas, and in particular, to an improved pulley system for use with outdoor and patio umbrellas.
2. Description of the Prior Art
Outdoor and patio umbrellas (hereinafter referred to collectively as patio umbrellas) have become increasingly popular in recent years as people have found new and useful applications for them. For example, patio umbrellas have traditionally been used at patios and backyards of homes to provide shade from sunlight. Patio umbrellas have also been used extensively at swimming pools and other play or recreation facilities to provide shade. Recently, hotels (and in particular, resorts) and restaurants have been major purchasers of these umbrellas.
In some locales, such as in tropical countries and resort areas where warm weather prevails for most of the year, these patio umbrellas will usually see extended usage. In addition, patio umbrellas are typically very heavy, large in size and bulky, thereby making them somewhat inconvenient to store and transport. However, patio umbrellas must carry sufficient weight and sturdiness to provide the necessary stability, otherwise they would not be appropriate for outdoor use.
For the above reasons, it is important that patio umbrellas be easy to open (i.e., deploy) and close (i.e., for storage). An important part of every patio umbrella is the pulley system. FIG. 1 illustrates a conventional pulley system that is commonly used for opening and closing patio umbrellas. FIG. 1 illustrates a section of the pole 10 of the umbrella along which a lower hub or runner 12 can be slid vertically upwardly or downwardly. A first pulley member 14 is secured to the pole 10 and a second pulley member 16 is secured to the runner 12. A pulley rope 18 has a first end 20 that is tied or knotted to a shaft 22 at a top end of the second pulley member 16. The rope 18 is then extended upwardly and passed through a lower wheel 24 of the first pulley member 14, and is then pulled back down towards the second pulley member 16 and passed through a wheel 26. The rope 18 is again extended upwardly and passed through an upper wheel 28 of the first pulley member 14, and is then pulled back down towards the bottom of the pole 10, where the user can manipulate the free end 30 of the rope 18.
As shown in FIG. 1, all the elements of the pulley system are provided on one side of the pole 10. Therefore, one drawback associated with the conventional pulley system of FIG. 1 is that all the forces operating on the pulley system are exerted on the same side of the pole 10. For example, to open the umbrella, the user must pull down on the free end 30 of the rope 18 in the direction of the arrow X, which decreases the length of the rope 18 between the first and second pulley members 14 and 16. This in turn causes the second pulley member 16 to be lifted vertically along the pole 10 towards the first pulley member 14 in the direction of arrow Y, thereby causing the ribs of the umbrella to be opened. As shown in FIG. 1, the forces indicated by arrows X and Y are on the same side of the pole 10 in that all the rotating wheels are inside pulley members 14 and 16 that are secured to the same side of the pole 10. Therefore, pulling down on the free end 30 may cause the umbrella to tilt to one side when the pulley rope 18 is being pulled down to open the umbrella. As a result, it can be difficult to pull and release the rope 18 to open and close, respectively, the umbrella. This is especially troublesome if the umbrella is heavy.
Thus, there remains a need to provide a patio umbrella that overcomes the drawbacks set forth above, and which provides a pulley system that provides better balance and weight distribution in use thereof in opening and closing the umbrella.